/Engine/Source/Runtime/AudioMixer/Public/AudioMixerBlueprintLibrary.h
Adds a submix effect preset to the given submix at the end of its submix effect chain. Returns the number of submix effects.
static int32 AddSubmixEffect ( const [UObject](API\Runtime\CoreUObject\UObject\UObject) * WorldContextObject, [USoundSubmix](API\Runtime\Engine\Sound\USoundSubmix) * SoundSubmix, [USoundEffectSubmixPreset](API\Runtime\Engine\Sound\USoundEffectSubmixPreset) * SubmixEffectPreset )